misk you head the nail right on the head.I'am haveing the same prombles
and mind is about 7'2" tall and flowering now for 5 wks.salt build up wrong PH
too strong nutrs and yes NOT ENOUGH LIGHT. Flos is best for clones and seedlying.Green Man on pot tv showed me the way,flos for the start grow to about 12"and than HPS for flowering and the finish.I"am going this way after
this grow. Keep on tokeing